Hi Peter,

Thanks for interesting of my problem. I try to make a tree invisible,
before adding nodes, but it was not reason of my problem. I didn't write
in my problem description,that sometimes are 4000 nodes in one level
(and already I populate the child nodes when user clicks on the parent
node). If you know solution of my problem now, please, mail me back.

If you have 4000 nodes at one level, I would suggest that a TreeView is
not an appropriate display mechanism - having to scroll through 4000 items
to find the one you want would be a nightmare for the users, wouldn't it?

One other thing that might be worth trying if you're willing to get
down-and-dirty at the API level is Brad Martinez's TVFastLoad example at
http://www.mvps.org/btmtz/treeview/

Regards

Stephen Bullen
Microsoft MVP - Excel
www.BMSLtd.co.uk